This invention relates to mechanized, or automated, stock-handling and cutting apparatus, particularly for cutting lumber to remove defects and to produce pieces of particular dimensions in accordance with a manifest. More particularly, the invention relates to a complete examination, transporting and cutting system in which a computer is fed data from an examination station relative to the location of defects along the length of a piece of lumber, and the computer then controls the complete sequence of advancing the lumber to a crosscut saw, stopping the stock for cutting at different places to ultimately produce the optimum yield and to remove the defects from each particular piece of stock, controlling the operation of the saw as well as that of a conveyor means which advances the stock relative to the saw.
The concept of automatic, machine-operated "defecting", or defect-removal, together with really precise and accurate optimum yield computation and cutting is one which has long been needed and in a general way long sought after in the lumbering and lumber-handling industries, as an indistinct ultimate goal. In partial satisfaction of such a goal, a number of devices have been proposed heretofore which were at least useful advances. For example, there have been systems proposed in which the stock was transported more or less automatically, by use of conveyors and the like, to an examining station and to a cutting station, where different individuals specialized in different tasks and were thus more efficient, one examining and marking the lumber where cutting was to take place, and the other sawing at the indicated marks. Subsequently, more inventive systems were advanced as for example systems in which the lumber is marked with machine-readable indicia at an examining station, and then transported through an automated sawing station which responds to such indicia automatically, sawing wherever each such indicia appears. A good example of a very effective type of such apparatus is disclosed in U.S. Pat. No. 3,780,777 assigned to Oliver Machinery Co. assignee herein.
Another type of system which has been proposed is illustrated in U.S. Pat. No. 3,329,181, in which the lumber itself is not actually marked, but instead, the "marking" or examining apparatus sends signals to a computer concerning the defects in a piece of stock, and the computer then indicates to a human sawer where cuts should be made. In this apparatus, however, all stock handling is done manually during the cutting operation, as is the actual operation of the saw.